Metallized dyes fob cotton



Patented Jan. 26, 1954 TENT o-F'Fl .METALLIZED DYES FOR/COTTON -Gharles HuStratton, East Greenbush,,N.,Y .,-;and William l'Wi-lliams, Easton, fPa", .assignors jto (ieneral:Aniline-,&;=Film CorporatiomfN ewjYorl z, N. Y., a corporation of Delaware N Drawing. Application March 20, 1950, Serial No..150,82 2

1 Glaim. (E31. 260'147 1 The. present invention relates to a copper'complexof a disazo dye. whichis-very light fast, relatively ,cheap- .to ma n,uiacture, and capable of yielding dyeings' in the very valuable reddishblue shades.

lt', has1beenliknown.ior some time that valuable blue to'blllez reen dyes ,canbe made by coppering the disazol'dyes produced by coupling ,tetrazotized dianisidine with two. molecules of a gnaphthol'suoh as a nonaphthol'disulfonic acids,

naphthol 'disulf onic'acids, and the like.

These dyesare very light fast, and relatively cheap to make. Furthermore, the shade and light fastness are retained when cloth bearing the -dyei-ngs is after-treated with a resin such as a urea-formaldehyde, melamine-formaldehyde, dicyandiamide-formaldehyde, and the like. These resins are applied for various purposes, as for instance, creaseproofing, imparting stillness, water repellencyg'and the like.

(One of the most valuable classes of blue dyes "required at the present time are those which are capable of yielding dyeings in a reddish-blue shade. .The Holder dyes, although possessing inanyadvantages,suffer from the fact that the dy'eings obtained therewith are only of a blue to blue-green-shade.

It has now been discovered that a copper complex dye obtained bytetrazotizing dianisidine and coupling the resulting tetrazo compound with 11 -;mol ,of .a .naphtholsdisulfonic acid and with 'l,.m01 ofv a. pyrazolone v containing a methyl ,group in:.the,. 3:,p.osition, yielddyeings of a very ;jpleasingyreddisheblueshade. i Such complex has the further advantage that it is cheaper to manufacture than the known dyes and gives a favorableresponse to after-treatment withresins derived from formaldehyde-and-an organic compound containing an amino group such as urea, melamine, dicyandiamine or thiourea.

Such complex and its preparation constitute the purposes and objects 'of the present invention.

The copper complex which is contemplated herein may be typified by the following structural formula:

l/ o t The d whic i .s qp-neredjto ie th c m le is made by tetrazotizing dianisjidine with so'dium nitrite and hydrochloric acid at a temperature below 10 (3., adding ,alkali suchnas.sodiumgbicarbonate to the reaction mixtureforihe purpose coupling is 2-naphthol-3,6-disu1fonic acid. Illustrative of the pyrazolone which we have found to be suitable is m-(4,5-dihydro-3-methyl- 5-oXo-1-pyrazolyl) -benzene sulfonic acid.

For effecting metallization of the dye prepared as above, a pa te ofthe. dye select diis r e ud e with water, ammonium hydroxide and copper sulfate at .a .ternperature.,of ..about 50,110 420?, ,C.

h dye i sol ted bysa t n outniil erina and drying to yield a powder.

The following example will-serveitoilustrate the invention claimed.

EwampZe.--Tetrazotizatiooz of danisidine 130 ml. of watercontaining sligram ofcthelsodium salt of di-n-butylnaphthalene=sulfoniczacid is heated to -C. lo mliof concentrated hydrochloric acid (-36%) is-thenadded. The temperaturerises' 2. v

The solution is vigorously-stirred: whilearapidly-a-dding 12.2grams .-05--mo'1) of-'dianisidine. =:TI he solution isstirred' until 1theadianisidineecomplete- 1y dissolves. The stirring is continued while 200 grams of finely chopped ice is added, as a result of which the temperature falls to 0 to 5 C.

24 ml. of concentrated hydrochloric acid is then added. Should the temperature rise above C., more ice is added to bring the temperature below 5 C.

7.1 grams of sodium nitrite as a roughly solution (23.6 ml.) is added dropwise to the solution over a period of 30 minutes. The solution is stirred and kept below 5 C. for an additional half hour. The excess nitrous acid is destroyed with a little sulfamic acid. The mixture is now ready for the first coupling operation.

First coupling The excess acid is destroyed by cautiously adding 21 grams of sodium bicarbonate The slow addition of the bicarbonate is necessary in order to avoid excessive foam. The solution at this stage should be acid to brilliant yellow paper but alkaline to delta paper. The latter is a paper impregnated with a dyestuff (2,4-dinitroaniline diazotized and coupled with 1-naphthol-3,6-disulfonic acid) which changes from yellow to blue in the pH range of 6 to 7.

The solution is stirred and maintained below 5 C. while a solution of 21 grams of 2-naphthol- 3,6-disulfonic acid (.0504 mol) and 100 ml. of

water is added dropwise in the course of an hour.

More alkali must be added to complete the coupling, and ordinarily 5 grams of sodium bicarbonate will sufiice.

The progress of the coupling can be readily followed. A drop of the reaction mixture is placed on filter paper. The insoluble halfcoupled product remains in the center while the soluble components are carried with the water as it spreads. Unreacted dianisidine tetrazo may be detected with an alkaline H-acid solution while R salt may be detected with any diazo solution. If the rim is colored, it means that cou- HOaS pling is actively taking place in the solution. At the conclusion of the reaction, ordinarily 30 minutes after the addition of the last of the R salt, the rim should be practically colorless and give none or only a very faint test for dianisidine tetrazo. A very slight excess of R salt is permissible.

Second coupling 4 Metallizaiion The paste is resludged with 600 ml. of water and then placed in a 2000 ml., 3-necked flask equipped with a motor driven stirrer, a watercooled condenser and a thermometer. 100 ml. of concentrated ammonium hydroxide (28.8%) is then stirred into the mixture.

A solution of 33 grams of hydrated copper sulfate (.135 mol) in ml. of water is added, bringing the total volume to 1100 ml. The temperature is raised to C. and held there for 37 hours while continuously stirring.

220 grams of salt is added and the product is filtered at 70 C. The paste, amounting to 296 grams, is dried at 85 C. to yield 962 grams of powder.

Dyeings 100 parts of cotton cloth is wetted out and immersed in a dye bath containing 2000 parts of water and 2 parts of direct copper dyestuff prepared as above. The temperature is raised to C. and held there for 45 minutes while 20 parts of salt is added to assist the exhaustion of the dyestufi. The dyed cloth is then rinsed and. dried.

A level reddish-blue shade of excellent fastness to light is obtained. The dye has excellent substantivity to cellulosic fibers and exhausts the dyebath almost completely.

Modifications of the invention will occur to persons skilled in the art, andwe, therefore, do not intend to be limited in the patent granted except as necessitated by the appended claim.

We claim:

The dye substantive to cotton of the following structure:

CHARLES H. STRATTON. WILLIAM W. WILLIAMS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,034,668 Reindel Mar. 17, 1936 2,428,130 Straub Sept. 30, 1947 2,476,259 Mayer et al. July 12, 1949 2,553,011 Schedler et al. May 15, 1951 FOREIGN PATENTS Number Country Date 502,677 Great Britain Mar. 21, 1939 

